Vancouver Island marmot

Location at the Zoo: Conservation Efforts

Region:

North America

Class:

Mammalia

Order:

Rodentia

Family:

Sciuridae

Genus:

Marmota

Scientific Name:

Marmota vancouverensis

Description

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The Vancouver Island marmot is a small, robust-bodied mammal. It is a member of the squirrel family. It has the distinction of being one of Canada's most endangered mammals. They are roughly the size of woodchucks — another Canadian marmot. They grow to lengths of 70 cm and weigh three to seven kg. Weights show large seasonal variation. They are characterized by a blunt snout ending in a black, flattened nose with large nostrils. The ears are small and rounded. The eyes are also small.

They have large beaver-like incisors, sharp claws, and very powerful shoulder and leg muscles. The tail is bushy and squirrel-like. It has a coarse, glossy coat of fur which is usually a rich chocolate-brown colour. There is a creamy white patch around the nose and mouth that extends to the underside of the neck. A light brown patch of fur is located on the top portion of the snout and there is often a mottled streak of creamy-white fur along the chest and belly. The legs are also sprinkled with lighter brown among the chestnut-brown coloured fur. Fur fades to a more rusty-rufous colour as the season progresses. Pups have very dark brown to black fur.

Distribution

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Marmotta vancouverensis are found only on Vancouver Island, which is a part of British Columbia, a Canadian province on the west coast.

Habitat

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Most are found between 1000 and 1400 metres in elevation, and on south to west-facing slopes. They can be found on the edges of mountain meadows, rocky slopes, logged sites, and thick clumps of alder trees.

There are three essential habitat features; grasses and forbes to eat; colluvial soil structure for construction of overnight and overwintering burrows; microclimatic conditions that permit summer foraging, thermoregulation, and successful hibernation.

Food

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They are herbivores, feeding on over 50 plant species. These include huckleberries, kinnikinnick fruit, cow parsnip, asters, tiger lilies, phlox, sweet peas, and woolly sunflowers. During the early spring they feed mainly on grasses (oat grass), sedges and early-blooming flowers, switching to flowers, berries, grasses, leaves, and fruit during the summer and fall. Water is obtained from the dew collected on the plants they eat.

Reproduction and Development

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Vancouver Island marmots live in colonies comprised of one or more family groups. Families usually contain one older male, one or more adult females, several adolescents, and any pups born during the year. The size and number of families varies between colonies and years.

Females are capable of breeding at age three, but most do not breed until their fourth summer. There is a non-reproductive interval of at least one year between litters. Mating occurs within a few weeks of emergence in the spring. Most litters are three to four pups. They are born after a gestation period of approximately 30 days. Pups are born blind and hairless and remain underground for about a month.

Young marmots remain within their colony for two years or so before dispersing to join or form other colonies. Dispersal distances and directions vary. They do not necessarily stop in the first available habitat. Males have a life span of five to six years, and females seven to nine years.

Adaptations

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Vancouver Island marmots live in underground burrows, and spend most of their lives there. They construct burrows in which to hibernate, bear young, hide from predators, and avoid environmental extremes. Burrows vary with purpose. Escape burrows may be a shallow excavation under a rock or tree root to avoid predators. Burrows used overnight or as birthing chambers are more elaborate, and often feature multiple entrances. Overwintering burrows are deeper. Natal and hibernation burrows are re-used. New burrows and look-out spots are a feature of new or expanding colonies.

They are true hibernators, for six months, the entire family of 15 or so huddle together in their winter burrow. With outside temperatures below freezing their body temperature can drop to 4.5 - 7.5 ˚C. Every three to four weeks they awaken to defecate and urinate. After hibernating from September-April, they only leave their burrows to feed in the early morning and late evening. Burrows are dug between rocks which provide protection from predators. Boulders play an integral role in their habitat as they provide lookout towers.

These are sociable marmots. They live in harmony, but are territorial. They have a “pecking order” lead by adult males, followed by females, then two year old males and females, then one year old males and at the bottom year old females.

Their hearing is very acute. Vancouver Island marmots are very vocal and have three different types of alarm calls varying in pitch. They also trill and have their own unique sound not emitted by any other marmot species: a "kee-aw".

Threats to Survival

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Predators and unsuccessful hibernation are the principle causes of mortality.
Both factors are exacerbated by the restricted range. The Vancouver Island marmot requires highly specialized habitat with small colonies found within Vancouver Island's scattered patches of sub-alpine meadow. Alteration of lands surrounding this habitat, small population size, and predator prey dynamics are the leading causes to the rapid decline in the population of this species. Predators include golden eagle, red tail hawk, cougar, and wolf.